The one that really breaks my heart is the SNR-300, a cutting-edge liquid metal sodium-cooled breeder reactor capable of unlocking the full potential of the majority isotope (U-238) rather than just the minority (U-235), giving us literally billions of years of current-day whole-earth power from known uranium resources (including seawater and erosion). It was 100% completed and ready to come up to power, but then Chernobyl happened and the people (of Germany) revolted. It is now an amusement park.
Another related timing coincidence is that a smaller sodium-cooled reactor in the USA (the EBR-2) demonstrated completely passive shutdown in loss of flow and loss of heat sink accidents without any control rods going in just 2 weeks before Chernobyl happened. Of course today almost no one has heard of it.
https://en.wikipedia.org/wiki/SNR-300
Another related timing coincidence is that a smaller sodium-cooled reactor in the USA (the EBR-2) demonstrated completely passive shutdown in loss of flow and loss of heat sink accidents without any control rods going in just 2 weeks before Chernobyl happened. Of course today almost no one has heard of it.
https://en.wikipedia.org/wiki/Experimental_Breeder_Reactor_I...